Wiktionary
piercement
n. (context geology English) A structure that has pierced into another.
Usage examples of "piercement".
The treasure chamber, the Pit itselfus, too, for Chrissakewe're all sitting on top of a goddamn piercement dome.
The treasure chamber, the Pit itself—us, too, for Chrissake—we're all sitting on top of a goddamn piercement dome.